A man questioned in connection to the case of missing baby Lisa Irwin has been charged with first-degree assault in an unrelated incident. Dane "Diggler" Greathouse, 28, has been charged for stabbing Greg R. May this weekend in Gladstone, Mo. Baby Lisa's parents, Jeremy Irwin and Deborah Bradley, claim missing baby Lisa was taken from her crib late Oct. 3, 2011 while Bradley was asleep and Irwin was at work. The one-year-old remains missing. Photo: Reuters

The Kansas City Police are still trying every possible option to get a clue to get to the one-year-old girl who went missing six weeks ago. But one of the retired Kansas City Police officers doubts the survival of missing baby Lisa Irwin.

Dave Bernard, who recently retired from Kansas City Police, and is very familiar with the girl's search operation, told KMBC News, You know, at this stage, I don't know. I doubt it. I doubt that she's still alive.

Bernard handled several investigations like of Lisa Irwin's, and was the lead investigator in the Precious Doe murder case. Though, Bernard retired in September, days before Lisa's disappearance, he still knows how police and investigators are approaching the case.

You can speculate on (whether) she was taken and abducted and whatever, but you concentrate on what is probable, what most likely happened here, and see where that takes you, KMBC quoted Bernard as saying.

As the investigators have already followed thousands of leads in the case, Bernard thinks the ending of the case might be what no one wants to think of.

Behind the scenes, I mean, you've got all these investigator that are out running down leads, he said with water in his eyes.

Calls may be coming in requiring further investigation, so they're out doing that or maybe a piece of evidence they've come across needs to be analyzed or tested, that sort of thing. So yeah, there's a lot of stuff going on that the public doesn't see, he added.

Lisa was found missing Oct. 4 when her father, Jeremy Irwin, returned from New York. The police focused much on homeless Johny Tanko who worked in the Irwin family's neighborhood. However, in mid-October, they said that Tanko had nothing to do with the vanishing of the baby. Kansas City Police Dept. spokesperson Steve Young told KCTV: We spoke to him and are moving on.

An award of $100,000 has been announced by an anonymous donor for the safe return of Baby Lisa.